McGraw-Hill, Health Professions Division, 2007. () Medication Safety in Pregnancy and Breastfeeding: The Evidence-Based, A to Z Clinician's Pocket Guide. New York: McGraw-Hill Medical, 2007. () Deferiprone controversy In 1996, a controversy erupted about the safety and effectiveness of deferiprone. Koren believed the drug was effective for certain patients. Nancy Olivieri of Toronto believed the drug was unsafe and ineffective. Following the initial controversy surrounding this drug trial in Toronto, Koren sent five anonymous harassing letters to colleagues and later denied having done so. Two independent inquiries by the CAUT and CPSO found that Koren had lied about sending the anonymous letters and only admitted guilt when confronted with DNA evidence against him. Both also found academic misconduct with respect to the way in which Koren published the research article cited above on the safety and effectiveness of deferiprone. CAUT accepted "the parties’ submissions that this misconduct should not be represented as fraudulent" and further remarked that "It was the behaviour that preceded the research misconduct that the Committee found most unsettling." A later study reported no evidence that long-term therapy with deferiprone caused progression of hepatic fibrosis. Cumulative worldwide experience has confirmed Koren's position on deferiprone, indicating that deferiprone is safe and effective for some patients. As a direct result of Olivieri's public media campaign, approval for the medication was stalled, meaning that North American children continued to be denied a medication which had since been approved around the world in dozens of countries and could be the only hope for survival for some children. Koren was officially reprimanded by the Ontario College of Physicians and Surgeons for writing harassing anonymous letters to Nancy Olivieri and three other colleagues, about which he then lied repeatedly to conceal his responsibility. The Ontario College of Physicians and Surgeons also cited him for additional misconduct in research. Scientific misconduct On December 16, 2018, an investigative article in The Toronto Star reported apparent problems in more than 400 papers coauthored by Koren, including that the papers "[were] inadequately peer-reviewed, fail to declare, perhaps even obscure, conflicts of interest and, in a handful of cases, contain lies about the methodology.” In 2019 Koren threatened a defamation lawsuit against the editor of Therapeutic Drug Monitoring for retracting one of Koren's papers. In February 2019, Koren agreed to relinquish his licence to practice medicine in Ontario in the face of an investigation by the College of